On 18 June Thialf, one of the world’s biggest heavy lift vessels, lifted the 9,000 tonne steel jacket into position on the North Sea Valemon field.
The 160 metre high construction is the biggest steel jacket installed in one lift on the Norwegian continental shelf (NCS) and first major part-delivery on the Valemon development project. The operation was carried out as planned and the project is on schedule.
The jacket, which was built by the Heerema Fabrication Group BV in Vlissingen in the Netherlands, was transported from the shipyard and out to the field by the crane barge.
“We are very pleased with this delivery from Heerema Fabrication Group BV, a new supplier to Statoil of steel jackets of this size,” says Anders Opedal, who heads up Projects.
“With Valemon the licensees are developing a new field in mature and exciting North Sea acreage. By making use of the existing infrastructure for processing and transport, the development is also preparing the ground for the cost-effective tie-back of new fields in both the Tampen and Heimdal areas. This will represent an important contribution to Statoil’s goal of developing the mature areas on the Norwegian continental shelf (NCS) in the years to come,” says Ivar Aasheim, head of field development on the NCS.
The Valemon platform contains the capacity for treating gas and condensate from discoveries in the adjacent area. Statoil and its licence partners are planning to conduct a programme of exploration in the area close to Valemon, where several prospects have been mapped.
Development of Valemon involves a fixed platform with a steel jacket for the separation of gas, condensate and water. The rich gas will be transported via a new pipeline to the existing pipeline from Huldra to Heimdal for further processing. The condensate will be piped to the Kvitebjørn platform for stabilisation and further transport via the Troll oil pipeline to the Mongstad refinery.
The volumes involved are large, with estimated recoverable reserves of about 210 mill. barrels of oil equivalents. At peak, Valemon will be expected to produce roughly 86,000 boe/d, thus helping to achieve Statoil’s target of maintaining production on the NCS in coming years.
Valemon will come on stream in the 4th quarter of 2014 and will last at least until 2025, helping also to prolong the lifetime of the processing platform on Heimdal.
The Valemon reservoir is complex not only because it is fragmented, but also because of the high pressure and high temperature there.
The plan is to develop Valemon with 11 platform producers and two injection wells for the depositing of cuttings and produced water in the shallow Utsira formation. A total of 20 well slots will be available on the platform to enable the drilling of further wells.
“I am glad that this first major delivery on the Valemon project has been completed and is now in place out on the field. This has been accomplished with good HSE results, on time and on budget,” says Opedal.
Location: PL 050 and PL 193, block 34/10 and 34/11. 10 km west of Kvitebjørn and 20 km southeast of Gullfaks
Licensees: Statoil, operator (53.775%), Petoro (30%), Centrica (13%) and Enterprise Oil (3.225%)
Reservoir: Gas/condensate, HPHT (high pressure, high temperature) conditions
Installation: Fixed platform with steel jacket, processing plant and accommodation facilities (40 cabins). The platform, which will normally be unmanned once the drilling phase is concluded, is remotely controlled from Kvitebjørn. The Valemon field will be included in the Kvitebjørn production organisation and be operated from Statoil’s base at Sandsli in Bergen
Transport: Rich gas via the Huldra pipeline to Heimdal for further processing. Condensate to Kvitebjørn for stabilisation and onward transport to Mongstad
Power supply by cable from the Kvitebjørn platform
The field was discovered by Statoil in 1985
Base case reserves: 26 billion standard cubic metres of gas, 5 million standard cubic metres of condensate, 1.3 million tonne NGL
Start of pre-drilling: August 2012. Production start-up: 4th quarter 2014
Estimated base case lifetime: 2014-2025
Investment: NOK 20.4 bill. (current)
Subsea World News Staff , June 19, 2012; Image: HFG